Mapster.Tool throwing System.IO.FileNotFoundException when using version 8.4.1

[stagep]

Since upgrading Mapster.Tool from 8.4.0-pre06 to 8.4.1, any mapping that references a type from a nuget package will throw an exception:
E.g. Unhandled exception. System.IO.FileNotFoundException: Could not load file or assembly 'Google.Protobuf, Version=3.24.3.0, Culture=neutral, PublicKeyToken=a7d26565bac4d604'. The system cannot find the file specified.

I am using the latest version of Mapster (7.4.1-pre01). I have tested and got the exception in .Net 7 and .Net 8 projects.

I am using Google.Protobuf as an example of a nuget package and using the example type of ByteString

In the project file i have
<Target Name="Mapster" AfterTargets="AfterBuild"> <Exec WorkingDirectory="$(ProjectDir)" Command="dotnet mapster mapper -a &quot;$(TargetDir)$(ProjectName).dll&quot;" /> </Target>

My mapping configuration is:

using Mapster;

namespace MapsterToolsException;

public class MapsterConfiguration : IRegister
{
 public void Register(TypeAdapterConfig config)
 {
 config.ForType<ByteString, byte[]>().MapWith(d => d.ToArray());
 }
}

You do not need to have any mappers defined to get the exception.

There is a workaround. Manually copying the Google.Protobuf.dll to the build folder (e.g. bin/Debug/net7.0) will eliminate the exception.

[stagep]

More details of the exception:

1>Unhandled exception. System.IO.FileNotFoundException: Could not load file or assembly 'Google.Protobuf, Version=3.24.3.0, Culture=neutral, PublicKeyToken=a7d26565bac4d604'. The system cannot find the file specified.
1>File name: 'Google.Protobuf, Version=3.24.3.0, Culture=neutral, PublicKeyToken=a7d26565bac4d604'
1> at MyProject.MapsterConfiguration.Register(TypeAdapterConfig config)
1> at Mapster.TypeAdapterConfig.Apply(IEnumerable`1 registers) in C:\Projects\Mapster\src\Mapster\TypeAdapterConfig.cs:line 752
1> at Mapster.TypeAdapterConfig.Scan(Assembly[] assemblies) in C:\Projects\Mapster\src\Mapster\TypeAdapterConfig.cs:line 731
1> at Mapster.Tool.Program.GenerateMappers(MapperOptions opt) in C:\Projects\Mapster\src\Mapster.Tool\Program.cs:line 66
1> at CommandLine.ParserResultExtensions.WithParsed[T](ParserResult`1 result, Action`1 action)
1> at Mapster.Tool.Program.Main(String[] args) in C:\Projects\Mapster\src\Mapster.Tool\Program.cs:line 19

[carumsoft]

I'm new to Mapster and i had similar problem.
You can not use AfterTargets="AfterBuild" path. This is not working.

I'm using on demand path with "dotnet build -p:CopyLocalLockFileAssemblies=true"

 <Target Name="Mapster">
	<Exec WorkingDirectory="$(ProjectDir)" Command="dotnet build -p:CopyLocalLockFileAssemblies=true" />
	<Exec WorkingDirectory="$(ProjectDir)" Command="dotnet tool restore" />
	<Exec WorkingDirectory="$(ProjectDir)" Command="dotnet mapster model -a &quot;$(TargetDir)$(ProjectName).dll&quot;" />
	<Exec WorkingDirectory="$(ProjectDir)" Command="dotnet mapster extension -a &quot;$(TargetDir)$(ProjectName).dll&quot;" />
	<Exec WorkingDirectory="$(ProjectDir)" Command="dotnet mapster mapper -a &quot;$(TargetDir)$(ProjectName).dll&quot;" />
 </Target>

[stagep]

Thanks for the pointer. I was able to resolve by adding
<CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>
to my project file and it now works as this copies the libraries referenced from the nuget packages to the build folder and the Mapster.Tool process can now find the necessary files. I did not modify anything else.

For future reference, this was a client side library so by default, the nuget files are not copied to the build folder.

[andrerav]

I'm sorry for your troubles @stagep, and thanks for the help @carumsoft. I think that this should be added to the documentation in case other users are experiencing this. @stagep Is it possible for you to share more details on how your csproj is set up now?

[stagep]

The project is a class library referenced by MAUI and Blazor WASM projects.

<Project Sdk="Microsoft.NET.Sdk">
 <PropertyGroup>
 <TargetFramework>net8.0</TargetFramework>
 <CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>
 </PropertyGroup>

 <ItemGroup>
 <PackageReference Include="Google.Protobuf" Version="3.24.3" />
 <PackageReference Include="Mapster" Version="7.4.1-pre01" />
 </ItemGroup>

 <Target Name="Mapster" AfterTargets="AfterBuild">
 <Exec WorkingDirectory="$(ProjectDir)" Command="dotnet tool restore" />
 <Exec WorkingDirectory="$(ProjectDir)" Command="dotnet mapster mapper -a &quot;$(TargetDir)$(ProjectName).dll&quot;" />
 </Target>
</Project>

Mapster.Tool 8.4.1-pre01 is installed.

[andrerav]

Awesome, thank you very much. I've added both of your workarounds to the wiki here: https://github.com/MapsterMapper/Mapster/wiki/Mapster.Tool#troubleshooting

[boylec]

I have a similar issue with the same versions of tooling but slightly different exception message for System.IO.FileNotFoundException, see referenced issue.